Adding and subtracting machine.



v No. 794.353. PATENTEDJULY 11, 1905.

A. F. HANSEN. ADDING AND SUBTRAGTING MACHINE.

APPLICATION FILED SEPT.22. 1904.

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APPLIUATION FILED SEPT. 22. 1904.

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L awuewtm JZZMrUT 1%775fi77 UNITED STATES Patented July 11, 1905.

PATENT OFFICE.

ALBERT F. HANSEN, OF OHIGKASI-IA, INDIAN TERRITORY.

ADDING AND SUBTRACTING MACHINE.

SPECIFICATION forming part of Letters Patent No. 794,353, dated July 11, 1905. Application led September 22, 1904. Serial No. 225,497.

To all whom, it may concern:

Be it known that I, ALBERT F. I-IANsEN,a citizen of the United States, residing at Chickasha, in Chickasaw Nation, Indian Territory, have invented certain new and useful Improvements in Adding and Subtracting Machines; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. I

My invention is an improved adding and subtracting machine; and it consists in the construction, combination, and arrangement of devices hereinafter described and claimed.

The object of my invention is to provide a machine of this character which is simple in construction, is readily operated, and is mathematically correct in computation, thereby enabling sums to be readily, rapidly, and accurately added, and which may also be used for subtracting.

In the accompanying drawings, Figure 1 is a front elevation of an adding and subtracting machine embodying my invention. Fig. 2 is a transverse sectional view of the same. Fig. 3 is a partial rear elevation of the same, and Fig. 1 is a detail vertical sectional view taken on the planeindicated by the line Z) 6 of Fig. 3.

- The face or front wall 1 of the machine has a suitable number of revoluble dials 2 for units, tens, hundreds, &c., any suitable number of the dials being employed, according to the desired capacity of the machine. Four of such dials are here shown, each having a plurality of scales numbered from O to 9. Dial a is for units, 7) is for tens, 0 is for hundreds, and (Z for thousands. Fixed pointers 3, with which the face or front wall of the machine is provided, coact with the scales of the revoluble dials, as will be understood.

In connection with each dial are a series of key-bars 4, nine in number and of different values, ranging consecutively from 1 to 9. These key-bars are here shown as extending through openings in the wall 1 and as pivoted at points substantially midway between-their ends, as at 5. The stroke of each key when its outer end is depressed by the operator is limited by a stop 6, the stops of the respective keys being here shown as secured on the front side of the wall 1 by screws 7, which permit of their being adjusted. To the rear end of each key-bar is pivoted a depending link 8. Each link has at its lower end a slot 9 of suitable length.

A rock-shaft 10 is mounted in suitable bearings, (indicated at 11 on the rear side of the wall 1.) This rock-shaft has rock-arms 12, one for each key-bar and link, said rock-arms being engaged with and connected to the links, as shown, the slots in the latter enabling said arms to be slidably connected to the said links. The rock-shaft for each dial and set of keybar-s is also provided, preferably near its opposite ends, with a pair of rearwardly-projecting rocking arms 13 1 1, each rigidly connected thereto.

Each dial has on its rear side concentric reversely-directed ratchet-gears 15 and 16. To

each arm 13 is pivoted a spring-pressed adding-pawl 17 to coact with the adding ratchetgear 15, and to each arm 1 1 is provided a similar spring-pressed subtracting-pawl 18 to coact with the subtracting reversely directed ratchet-gear 16. A set-shaft 19, here shown as mounted in bearings 20 on the rear side of the wall 1, has cams 21 22 disposed angularly with reference to each other and adapted to respectively disengage the adding and sub tracting pawls from their respective coacting reversely-directed ratchet-gears, so that when one of said pawls is engaged the other will be disengaged. It will be understood that said pawls when respectively operated by the rockshaft and the finger-bars will cause the dial with which they are associated to revolve in Y reverse directions by a step-by-step movement to an extent corresponding to the value of the key-lever which is operated. The set-shaft 19 has a set-arm 23, which operates in a slot 24: in the front wall 1. This enables theshaft 19 to be appropriately set to adapt the machine for adding or subtracting, as may be desired. 1

In order to cause the dials to carry the tens from one to another in ascending or descending series, according to whether the machine is used for adding or subtracting, I provide the carrying mechanisms which I will now describe, one of said carrying mechanisms being used between and in connection with each two adjacent dials.

A pair of spring-pawls 26 to respectively engage the adding and subtracting gears 15 16 of one of the dials are united to a slide 2'7, mounted for reciprocating longitudinal movement on the rear side of the wall 1, and which has a tappet 28 at one end and has a spring 29 to move said guide and the said spring-rmwls in one direction. A shipper 30, which has oppositely-inclined camfaces 31 32 respectively engaged with the said spring-pawls, is mounted on the rear side of the wall 1 for movement in a plane at right angles to that of the slide and the spring pawls and has an opm'atil'ig-key 33 for mow ing it in reverse directions to engage one of the said pawls with one of said gears and disengage the other pawl from the other gear. Each of said slides is moved against the tension of the spring 29 bycams 34, one 01 which is provided for each scale on each of the dials, excepting the dial of highest value. As each dial is revolved by a step-by-step movement by the operating-keys and devices hereinbe'li'ore described to an extent equal to the value of one of its scales, one of its cams 34: in passing the slide engages the tappet of the latter and moves said slide, together with the spring-pawls against the tension 01" the spring 29 a suiiicient distance to cause the engaged pawl to move the next adjacent dial one step, as will be understood, the spring serving to return the slide and the pawls to their initial positions.

From the foregoing description, taken in connection with the accompanying drawings, the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion,

and the minor details of construction may be resorted to without (:le1:)arting from the p rinciple or sacrificing any of the advantages of this invention.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A machine of the class described, having a revoluble dial provided with concentric revcrsely-directed ratchet-gears, a rock-shaft l'laving rockarms 12, 13 and 14:, springpressed pa wls to engage the respective ratchetgears and respectively connected to the arms 13 and 14-, keys having links connected to and having lost motion on the arms 12, and a shipper to alternately engage the pawls with the respective revcrsely-directed ratcl'let-gcars.

2. A machine of the class described having a plurality of dials, each provided with re- 'ersely-directed ratchet-gears, pawls to respectively engage the said ratchet-gears, keys and connecting devices to operate the pawls, and means to put either of the pawls out of engagel'nent with its coacting ratchet-granwhereby the dial may be rotated by a stepbystep movement in either direction by operating the keys, one of said dials having a cam, in combination with spring pressed pawls, to rcs 'iectively engage the respective ratchet-gears of the next adjacent dial, and having an element operated by said cam to move said pawls against the tension of their spring, and a shipper to engage either of said pawls with one ratchet-gear and disengage the other from the other ratchet-gear, for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ALBERT F. HANSEN.

W'itnesses:

Lns'rnn L. Pinon, A. L. HERB. 

